DOI

10.5703/1288284314208

Abstract

The continuing loss of pavement performance observed in the U.S. transportation infrastructure system raises the issue of the subdrainage design. Experience with the Indiana highways indicates that the lack of adequa the sub-drainage is probably a major cause of pavement distress. In order to provide highway engineers with a methodology to analyze the water migration and drainage into pavement systems a new numerical model has been developed. The numerical scheme is a finite difference formulation of the equations of water flow in unsaturated porous media. The resulting system of equations used is nonlinear and state-of-the-art numerical techniques have been used in order to obtain solutions with accelerated convergence and improved stability of the algorithms employed. Theoretical background of unsaturated flow and its numerical analysis is included in the present report. A computer program, PURDRALN, has been developed to implement the model in a software environment. The validity of proposed numerical model and the developed computer program have been tested using available experimental data. Examples of applications for analyzing moisture infiltration with different pavement geometries are presented.